21516670670 has 64 divisors (see below), whose sum is σ = 45776814336. Its totient is φ = 7192711680.

The previous prime is 21516670639. The next prime is 21516670697. The reversal of 21516670670 is 7607661512.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 53384 + ... + 214203.

It is an arithmetic number, because the mean of its divisors is an integer number (715262724).

Almost surely, 2^21516670670 is an apocalyptic number.

21516670670 is an abundant number, since it is smaller than the sum of its proper divisors (24260143666).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21516670670 is a wasteful number, since it uses less digits than its factorization.

21516670670 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 267665.

The product of its (nonzero) digits is 105840, while the sum is 41.

The spelling of 21516670670 in words is "twenty-one billion, five hundred sixteen million, six hundred seventy thousand, six hundred seventy".